Sticking to formula, "Thor" provides a few satisfying twists

Movies based on Marvel characters are about as sure a thing as there is in the uncertain world of theatrical exhibition. But what separates the good ones (Iron Man) from the bad ones (Daredevil, Ghost Rider)? It comes down to tone and casting, and Thor shows that director Kenneth Branagh grasps this. He nails a unique tone, and he's got a lead actor who seems to understand how to play a god.

To be precise, as the mythology unfolds, he's not exactly a god. Thor (Chris Hemsworth) is one of the immortal inhabitants of Asgard, his father Odin (Anthony Hopkins) their monarch. Centuries ago the Asgardians defeated the Frost Giants who sought to destroy humanity, and a truce has existed ever since. But when the cocky Thor threatens that fragile peace, Odin banishes him to Earth and strips him of his powers. He's found in the New Mexico desert by astrophysicist Jane Foster (Natalie Portman), spouting gibberish about his origins and trying to locate the mystical hammer Mjolnir that will return him to his rightful place.

That's a bit of a twist on the typical superhero origin story. Rather than following a normal person as he adjusts to having extraordinary abilities, this one does the reverse. And it's here that Hemsworth proves himself not just an impressive physical specimen, but a fairly deft comedian. The writers give him some solid fish-out-of-water moments, and Hemsworth plays them with the twinkle of someone accustomed to having the world bend to his will.

Branagh, meanwhile, shows with the Asgard scenes why a guy with a bunch of Shakespeare adaptations to his credit was the right choice. The story is essentially one of jealousy and treachery inside the walls of a castle, as Thor's trickster brother, Loki (Tom Hiddleston), tries to manipulate his way onto the throne. That's a milieu Branagh certainly knows his way around. There's such dramatic grandeur in those scenes that the juxtaposition with the earth-bound scenes is at times jarring.

Perhaps the frustration is that the unique tone of the Asgard scenes is the only opportunity for Thor to carve out a distinctive identity. While the conflict among Thor, his friends and the Frost Giants offers a new context for superhero action, the climactic battle could be an outtake from Iron Man 2. The romance between Thor and Jane feels rushed, and the tidbits tossed to the fanboys are often as distracting as they are amusing.

There's little question that Thor will succeed, largely because it adheres to a familiar formula. But could there have been more room for the satisfying ways in which Thor is one of a kind?